ONE leads a £20,000-a-year private college in Henley-on-Thames where the pupils wear blazers inspired by the local regatta.

The other is in charge of pupils at a no-holds-barred comprehensive in Greenock.

But real-life head Gregg Davies gave TV teacher Michael Byrne the lessons he needed to lead Waterloo Road.

Actor Alec Newman turned to Gregg for inspiration as he prepared to take the reins of the BBC school.

After a chance meeting in a pub, Alec asked Gregg, 51, if he could shadow him for a day at his Shiplake College.

Alec says the time he and fellow actress Daniela Denby-Ashe spent there helped them prepare for the current series, which relocates Waterloo Road to Scotland.

Dad-of-one Gregg yesterday revealed he is delighted to have inspired Glasgow-born Alec and insists the TV star would make a great teacher in real life.

He said: “I was in the pub with my daughter on Christmas Eve when she spotted Alec and told me he played the teacher in her favourite programme. I had never seen the show but thought I would go over and speak to him, one headmaster to another.

“We chatted for ages. After a while, he asked me if he and Daniela could come and watch me at work.”

Gregg, who used to be deputy headmaster of Fettes College, in Edinburgh, said: “I was delighted to help them out. The pupils were very excited when I told them who was coming in.

“They went along to assembly, spent the morning with the younger pupils and the afternoon with the sixth-formers.

“Alec asked me lots of questions about what makes a good headmaster. He was brilliant with the kids and, in my opinion, would make a great teacher in real life.

“The BBC could not have chosen anyone better to play the role.”

In the new series, Daniela’s character Lorraine Donegan, who has financed the school’s relocation from Manchester, is at constant loggerheads with Alec’s character about how to run the place.

St Andrews University graduate Gregg, who is dad to Anna, 14, said: “I let Daniela go through all our finances so she could get to grips with what it takes to run an independent school.

“I was able to advise Alec that, even though he is not in charge of the purse strings, he is still in charge and should take no nonsense from anyone.”

Alec, 37, whose dad Sandy was in 60s chart-toppers Marmalade, says Gregg is one of the most inspirational people he has ever met.

He said: “Simply watching this man work as he walked about the school was invaluable. He would be talking to me one minute and then, out of the corner of his eye, would see someone with a shirt untucked or a tie not done properly.

“He’d say, ‘Good morning Mr – whatever the kid’s name was – you are going to put that tie up to the collar.’ I liked all that.”

Gregg, who is a qualified Scotland rugby referee, has been head of Shiplake for eight years.

He is not afraid to challenge traditional teaching methods and has made major changes since he took the helm in 2004.

Gregg, who is married to magistrate Alison, 47, started by changing the uniform – and expelling six pupils.

He said: “The very first thing I did was get rid of the blue polyester uniform and change it to a bright stripey blazer.

“I wanted the kids to stand out and be proud to be at Shiplake. The stripes were inspired by the Henley Regatta. We are the fourth best rowing school in the UK and boast several Olympic medallist past pupils.”

Gregg, who has a house in Dunino, Fife, added: “The second thing I did was expel six 16 and 17-year-olds who brought drugs into the school.

“It was a big move to make so early in my career but it paid off and I have not had a minute’s trouble since.”

The headmaster, whose wife used to sit on Scotland’s Children’s Panel, delivers some hands-on teaching in his 400-strong school, in Oxfordshire.

He said: “Shiplake is a boys-only school up until sixth form, when we accept girls. I am a strong believer in single sex education for boys as they are very self-conscious about getting questions wrong in class, especially in front of girls.

Posh private school Shiplake College

“In our school, each pupil has a red cup and a green cup on the desk. When a pupil has fully understood a topic, they turn the green cup over.

“If they are having trouble, they turn the red cup over and the teacher will go over the topic again, without the boy being singled out.”

He added: “There is no better feeling in the world than realising you are helping pupils achieve their dreams.